Python STL container method overloading fix

Fix method overloading of methods that take STL containers of different types.
Due to some error handling that was not cleared during typehecking.

CHANGES.current

@@ -7,6 +7,56 @@ the issue number to the end of the URL: https://github.com/swig/swig/issues/
 Version 4.0.1 (in progress)
 ===========================
 
+2019-08-07: wsfulton
+            [Python] Fix method overloading of methods that take STL containers of different
+            types. The following usage (using std::vector) would fail when using -builtin:
+
+              %include <std_string.i>
+              %include <std_vector.i>
+
+              %inline %{
+              struct X {};
+              %}
+
+              %template(VectorX) std::vector<X>;
+              %template(VectorInt) std::vector<int>;
+
+              %inline %{
+              using namespace std;
+              string VectorOverload(vector<X> v);
+              string VectorOverload(vector<int> v);
+              %}
+
+            The following would incorrectly fail:
+
+              s = VectorOverload([1, 2, 3])
+
+            With:
+
+              Traceback (most recent call last):
+                File "runme3.py", line 20, in <module>
+                  ret = VectorOverload([1, 2, 3])
+              TypeError: Wrong number or type of arguments for overloaded function 'VectorOverload'.
+                Possible C/C++ prototypes are:
+                  VectorOverload(std::vector< Number,std::allocator< Number > >)
+                  VectorOverload(std::vector< int,std::allocator< int > >)
+
+            The problem was due to some error handling that was not cleared during typehecking.
+            In this case an error was not cleared when the elements in the list failed the
+            typecheck for converting to X. Only occurs in Python 3+.
+
+            In some combinations of overloaded methods, the following type of error message would
+            occur:
+
+              RuntimeError: in sequence element 0
+
+              The above exception was the direct cause of the following exception:
+
+              Traceback (most recent call last):
+                File "runme3.py", line 23, in <module>
+                  check(VectorOverload(v), "vector<X>")
+              SystemError: <built-in function VectorOverload> returned a result with an error set
+
 2019-08-01: wsfulton
             #1602 Fix regression in 4.0.0 where a template function containing a parameter
             with the same name as the function name led to the parameter name used in the

Examples/test-suite/common.mk

@@ -643,6 +643,7 @@ CPP_STD_TEST_CASES += \
 	director_string \
 	ignore_template_constructor \
 	li_std_combinations \
+	li_std_containers_overload \
 	li_std_deque \
 	li_std_except \
 	li_std_except_as_class \

Examples/test-suite/li_std_containers_overload.i

@@ -0,0 +1,33 @@
+%module li_std_containers_overload
+
+// Suppress warning that ought not to appear, but there is no easy fix
+%warnfilter(SWIGWARN_LANG_OVERLOAD_SHADOW) VectorOverload;
+
+%include <std_string.i>
+%include <std_vector.i>
+
+%inline %{
+struct X {};
+struct Y {};
+%}
+
+%template(VectorX) std::vector<X>;
+%template(VectorY) std::vector<Y>;
+%template(VectorString) std::vector<std::string>;
+%template(VectorInt) std::vector<int>;
+
+%inline %{
+using namespace std;
+string VectorOverload(vector<X> v) {
+  return "vector<X>";
+}
+string VectorOverload(vector<Y> v) {
+  return "vector<Y>";
+}
+string VectorOverload(vector<string> v) {
+  return "vector<string>";
+}
+string VectorOverload(vector<int> v) {
+  return "vector<int>";
+}
+%}

Examples/test-suite/octave/li_std_containers_overload_runme.m

@@ -0,0 +1,37 @@
+# do not dump Octave core
+if exist("crash_dumps_octave_core", "builtin")
+  crash_dumps_octave_core(0);
+endif
+
+li_std_containers_overload
+
+function check(got, expected)
+  if (!strcmp(got, expected))
+    error("Failed check. '%s' != '%s'", got, expected)
+  endif
+end
+
+v = VectorX();
+check(VectorOverload(v), "vector<X>");
+
+v = VectorY();
+check(VectorOverload(v), "vector<Y>");
+
+v = VectorInt();
+check(VectorOverload(v), "vector<int>");
+
+v = VectorString();
+check(VectorOverload(v), "vector<string>");
+
+# TODO: Conversion from an Octave sequence not implemented yet
+# v = {X()};
+# check(VectorOverload(v), "vector<X>");
+
+# v = {Y()};
+# check(VectorOverload(v), "vector<Y>");
+
+# v = {1, 2, 3};
+# check(VectorOverload(v), "vector<int>");
+
+# v = {"aaa", "bbb", "ccc"};
+# check(VectorOverload(v), "vector<string>");

Examples/test-suite/python/li_std_containers_overload_runme.py

@@ -0,0 +1,29 @@
+from li_std_containers_overload import *
+
+def check(got, expected):
+    if got != expected:
+        raise RuntimeError("Failed check. '{}' != '{}'".format(got, expected))
+
+v = VectorX()
+check(VectorOverload(v), "vector<X>")
+
+v = VectorY()
+check(VectorOverload(v), "vector<Y>")
+
+v = VectorInt()
+check(VectorOverload(v), "vector<int>")
+
+v = VectorString()
+check(VectorOverload(v), "vector<string>")
+
+v = [X()]
+check(VectorOverload(v), "vector<X>")
+
+v = [Y()]
+check(VectorOverload(v), "vector<Y>")
+
+v = [1, 2, 3]
+check(VectorOverload(v), "vector<int>")
+
+v = ["aaa", "bbb", "ccc"]
+check(VectorOverload(v), "vector<string>")

Examples/test-suite/ruby/li_std_containers_overload_runme.rb

@@ -0,0 +1,44 @@
+#!/usr/bin/env ruby
+#
+# Put description here
+#
+# 
+# 
+# 
+#
+
+require 'swig_assert'
+
+require 'li_std_containers_overload'
+
+include Li_std_containers_overload
+
+def check(got, expected)
+  if (got != expected)
+    raise RuntimeError, "Failed check. '#{got}' != '#{expected}'"
+  end
+end
+
+v = VectorX.new()
+check(VectorOverload(v), "vector<X>")
+
+v = VectorY.new()
+check(VectorOverload(v), "vector<Y>")
+
+v = VectorInt.new()
+check(VectorOverload(v), "vector<int>")
+
+v = VectorString.new()
+check(VectorOverload(v), "vector<string>")
+
+v = [X.new()]
+check(VectorOverload(v), "vector<X>")
+
+v = [Y.new()]
+check(VectorOverload(v), "vector<Y>")
+
+v = [1, 2, 3]
+check(VectorOverload(v), "vector<int>")
+
+v = ["aaa", "bbb", "ccc"]
+check(VectorOverload(v), "vector<string>")

Lib/octave/octcontainer.swg

@@ -401,21 +401,15 @@ namespace swig
       return const_reference(_seq, n);
     }
 
-    bool check(bool set_err = true) const
+    bool check() const
     {
       int s = size();
       for (int i = 0; i < s; ++i) {
 	//	swig::SwigVar_PyObject item = OctSequence_GetItem(_seq, i);
 	octave_value item; // * todo
-	if (!swig::check<value_type>(item)) {
-	  if (set_err) {
-	    char msg[1024];
-	    sprintf(msg, "in sequence element %d", i);
-	    SWIG_Error(SWIG_RuntimeError, msg);
-	  }
+	if (!swig::check<value_type>(item))
 	  return false;
       }
-      }
       return true;
     }
 

Lib/python/pycontainer.swg

@@ -672,20 +672,14 @@ namespace swig
       return const_reference(_seq, n);
     }
 
-    bool check(bool set_err = true) const
+    bool check() const
     {
       Py_ssize_t s = size();
       for (Py_ssize_t i = 0; i < s; ++i) {
 	swig::SwigVar_PyObject item = PySequence_GetItem(_seq, i);
-	if (!swig::check<value_type>(item)) {
-	  if (set_err) {
-	    char msg[1024];
-	    sprintf(msg, "in sequence element %d", (int)i);
-	    SWIG_Error(SWIG_RuntimeError, msg);
-	  }
+	if (!swig::check<value_type>(item))
 	  return false;
       }
-      }
       return true;
     }
 

Lib/ruby/rubycontainer.swg

@@ -395,20 +395,14 @@ namespace swig
       return const_reference(_seq, n);
     }
 
-    bool check(bool set_err = false) const
+    bool check() const
     {
       int s = (int) size();
       for (int i = 0; i < s; ++i) {
 	VALUE item = rb_ary_entry(_seq, i );
-	if (!swig::check<value_type>(item)) {
-	  if (set_err) {
-	    char msg[1024];
-	    sprintf(msg, "in sequence element %d", i);
-	    SWIG_Error(SWIG_RuntimeError, msg);
-	  }
+	if (!swig::check<value_type>(item))
 	  return false;
       }
-      }
       return true;
     }